Taobao casings are cheap, but dried casings are short-headed scraps produced in the process of producing casings, which are made of unnecessary things. Casing is the inner layer of the large intestine, which is not as delicious as the large intestine itself. It can only be used to hold other ingredients. Compared with the natural casing, the artificial casing is cheaper, almost half of the natural casing, and it is stronger to use, a bit like a transparent plastic bag.